Problem: Express your answer as a mixed number simplified to lowest terms. $9\dfrac{7}{20}-5\dfrac{5}{6} = {?}$
Explanation: Find a common denominator for the fractions: $= {9\dfrac{21}{60}}-{5\dfrac{50}{60}}$ Convert ${9\dfrac{21}{60}}$ to ${8 + \dfrac{60}{60} + \dfrac{21}{60}}$ So the problem becomes: ${8\dfrac{81}{60}}-{5\dfrac{50}{60}}$ Separate the whole numbers from the fractional parts: $= {8} + {\dfrac{81}{60}} - {5} - {\dfrac{50}{60}}$ Bring the whole numbers together and the fractions together: $= {8} - {5} + {\dfrac{81}{60}} - {\dfrac{50}{60}}$ Subtract the whole numbers: $=3 + {\dfrac{81}{60}} - {\dfrac{50}{60}}$ Subtract the fractions: $= 3+\dfrac{31}{60}$ Combine the whole and fractional parts into a mixed number: $= 3\dfrac{31}{60}$